struts2的validate.xml验证无效，且报异常

struts2的validate.xml验证无效，且报异常为
Caused by: org.xml.sax.SAXParseException: The markup declarations contained or pointed to by the document type declaration must be well-formed.
解决办法：
主要validate.xml声明变化导致，将声明
<!DOCTYPE validators PUBLIC "-//OpenSymphony Group//XWork Validator 1.0.2//EN" 
"http://www.opensymphony.com/xwork/xwork-validator-1.0.2.dtd">
改为
<!DOCTYPE validators PUBLIC "-//Apache Struts//XWork Validator 1.0.2//EN"
        "http://struts.apache.org/dtds/xwork-validator-1.0.2.dtd">